IDENTIFICATION OF GENERATION-RECOMBINATION CENTERS AND TRAPS IN VIRGIN AND FOWLER-NORDHEIM STRESSED METAL-OXIDE-SEMICONDUCTOR FIELD-EFFECT TRANSISTORS BY LOW-TEMPERATURE CHARGE-PUMPING TECHNIQUE

Low temperature charge pumping (CP) current measurements were carried out on 100 mu m/10 mu m N-channel metal-oxide-semiconductor (NMOS) tra nsistors to investigate the interface state density. Interface states comprise traps and generation-recombination (g-r) centers. By measurin g the CP current at different pulse frequencies at low temperatures, w here the emission time constant of the traps is larger, the distributi on of traps is determined distinct from that of the g-r centers. The f ormation of traps and g-r centers due to Fowler-Nordheim (F-N) injecti on at 77 K was studied by using this technique. It was shown that, imm ediately after the stress, F-N stress at 77 K creates more traps than g-r centers. When the temperature was raised to room temperature follo wing stress at 77 K, the transformation from traps to g-r centers was observed. In alternating positive and negative F-N stress, positive F- N stress anneal out some of the traps generated during the previous ne gative F-N stress.